Electric air-heating furnace



W. DOH ERTY ELECTRIC AIR HEATING FURNACE Filed Sept. 27, 1926 5Sheets-Sheet INVENTOR mym ATTORNEY Oct. 16, 1928. 1,688,270

w. DOHERTY ELECTRIC A IR HEATING FURNACE Filed Sept. 27, 1926 3Sheets-Sheet 2 Oct. 16, 1928.

W. DOHERTY ELECTRIC AIR HEATING FURNACE Filed Sept. 27, 1926 3Sheets-Sheet 5 I ZGZZZ'QwJaWWy INVENTOR W BY W ATTORNEY Patented Oct.16, 1928.

UNITED STATES WILLIAM DOHERTY, OF WEST PHILADELPHIA, PENNSYLVAN IA.

ELECTRIC AIR-HEATING FURNACE.

Application filed September 27, 1926. Serial No. 138,012.

This invention relates to heating apparatus, particularly to heaters ofthe electrically operated type, and has for its object the provision ofa novel furnace or heating device adapted for household or other use forthe purpose of heating air which may be distributed to a plurality ofrooms or other places to be heated.

I An important object of the invention is to provide a heating device ofthis character provided with a peculiarly constructed and arrangedheating unit of resistance material capable of developing a high degreeof heat upon passage of an electric current there :5 through.

A further object is to provide a heater of this character having a novelconstruction of walls whereby the heat will be conserved and preventedfrom becoming dissipated into the an atmosphere.

An additional object is the provision of a device of this characterwhich will be comparatively simple and inexpensive to manufacture, andassemble, easy to control or operate, positive in action, eflicient anddurable in service, and a general improvement in the art.

With the above and other objects and advantages in view, the inventionconsists in the details of construction, the arrangement and combinationof parts to be hereinafter more fully described and claimed, andillustrated in the accompanying drawings, in which:

Figure 1 is a vertical sectional view taken through the heater.

Figure 2 is a similar view taken at right angles to Figure 1.

1 Figure 3 is a horizontal cross sectional view taken on the line 33 ofFigure 1.

Figure 4 is a detail sectional viewtaken on the line 4-4 of Figure 2.

Referring more particularly to the drawings, I have shown the device ascomprising a casing designated generally by the numeral 10, this casinbeing preferably, though not necessarily, o cylindrical shape andprovided with an arched or crowned roof 11 and a base or bottom 12,While it is conceivable that the exact construction of this casing, roofand base may be varied within quite wide limits, it is preferable thatthe bottom or base 12 be constructed of concrete, theroof or top of thesame material, and the side portions or main body 10 either of concreteor other cementitious material or else of layers of asbestos or otherheat resisting material indicated at 13, between which is a preferablymetallic shell 14. In the present instance, I have illustrated bands 15extending horizontally about the body of the structure for reinforcingpurposes, certain of these bands being located at the outside and othersbeing located at the inside, the entire purpose being to make a strongand rigid structure capable of withstanding. severetemperature changeswithout dangerof buckling or disintegration. Obviously, other specificdetails of construction may be resorted to if found advisable inasmuchas there is no particular limitation desired in this respect. It is ofcourse necessary that the casing be provided with means whereby accessmay be had' to the interior thereof, and for this reason there is shownan opening 16 at some convenient point in one side, this opening beingclosed by a preferably hinged door structure 17 of the same generalcharacteristic as the casing construction itself, the door beingprovided with suitable latch means indicated at 18 for the purpose ofholding it normally closed.

Located within the central lower portion of the casing 10 is a chamber19 which may be formed by forming an upstanding cylindrical wall 20 uponthe base or bottom 12 and extending through one side of the casing 10and communicating with the chamber 19 is a cold air inlet pipe 21 of anyordinary or preferred construction preferably provided with a damper orvalve 22 capable of manual or other manipulation for the purpose ofregulating the inflow of fresh air to be heated. Extending'into andleading from the upper portion of the casing 10 is any desired number ofoutlet pipes 23 which, if the-device is used in a dwelling house, wouldnaturally lead to the different rooms to be heated. The length andarrangement, as well as the size of these pipes 23 is immaterial as manyvariations may be resorted to. Clearly, if any such means is desired,valves or'the like may be interposed in the air outlet pipe 23 for thepurpose of controlling the passage of heated air fromjhe casing.

Mounted upon the upper end of the cylindrical wall structure 20 whichdefines the chamber 19 is a metallic plate 24: which preferably has adepending flange portion 25 embracingly engaging about the cylindricalwall 20 and which also has an upstanding flange 26 constitutingretaining means for a mass 27 of disk-like form, of refractory materialsuch as fire clay'or the like. The metal disk 24 and the'material 27 areboth formed with registering holes 28 and 29 respectively, so that airentering the chamber 19 through the pipe 21 may pass upwardly and intbthe upper portion of the casing.

The heating means comprises a plurality of upright serpentine barmembers 30 of suitable resistance metal mounted on top of the refractorymember 27 by any suitable means, it being preferable that these membersbe spaced apart by blocks 31 of suitable insulating and refractorymaterial held in assembled relation as by stays or bolts 32. In thepresent instance there are three groups of serpentine resistance bars ormembers 30 disclosed all connected in parallel by branch conductors 33and 35L connected with main conductors 35 and 36 respectively which leadto and through u n-insulated bushing 37 extending. through the side ofthe casing 10. Obviously, any switch device may be connected with theseconductors for cutting ofi' the supply of current thereto and it isconceivable that resistance means be employed for regulating thequantity of current passing through the resistance bars or elements 30.i

In the operation of the device, it will of course be apparent that whencurrent is fed ,to the resistance elements 30 they will become hot andin fact incandescent, their heat being communicated to the blocks 31 ofrefractory insulating material, the whole. mass being very hot. The airentering through the pipe or conduit 21 into the chamber 19 passesthrough the registering holes 28 and 29 and upthrough and between oramong the heating units or resistance elements 30, theair beingconsequently heated and being then discharged through the pi e 23 to thevarious rooms in the building to lie heated. It is really believed thatthe con struction, operation and advantages of this portion of theapparatus will be readily apparent to one skilled in the art withoutfurther explanation. However, it is of course apparent that some meansmust be provided for supplying current to the device and in Figures 5and 6 I have illustrated a very con-- venicnt battery structure of theplunger type which may be used in case house current is not available.

From the foregoing description and a study of the drawings, it will bereadily apparent that I have thus provided a very simply constructed andinexpensive air heating device which is well adapted for use in heatingdwelling houses or other places employing the hot air system.Furthermore,

it will be noted that I have also disclosed a very simply constructed,inexpensive and yet highly eflicient plunge battery for the purpose ofsupplying current to the heating elements. It is really believed thatthecon struction, operation and advantages will be readily apparent to oneskilled in the art without further explanation.

'While I have shown and described the preferred embodiment of theinvention, it should be understood that I reserve the right to make suchchanges in the form, construction and arrangement of parts as will notdepart from the spirit of the invention or the scope of the subjoinedclaims.

Having thus described the invention, I claim:

1. In a heater of the character described, a casing provided near itstop with a plurality of radially extending outlet pipes, anupstanding'chamber member within the central lower portion of thecasing, a cold air inlet pipe extending thru one side of the easing intosaid chamber member, a metal cover on said chamber member having aplurality of holes therein, a refractory top on said cover having holesregistering with said first named holes, and heating means mounted aboveand supported upon said chamber structure and including a serpentineresistance member arranged in upright position and secured upon saidrefractory top with its alternate convolutions located above andregistering with said holes.

2. In a heater of the character described, a casing provided near itstop with a plurality of radially extending outlet pipes, an upstandingchamber member within the central lower portion of the casing, a coldair inlet pipe extending thru one side of the easing into said chambermember, a metal cover on said chamber member having a plurality of holestherein, a refractory top on said cover having holes registering withsaid first named holes, and heating means mounted above and supportedupon said chamber structure and including a serpentine resistance memberarranged in upright position and secured upon said refractory top withits alternate convolutions located above and registering with saidholes, and spacing and confining means for the serpentine heating unitcomprising a series of block-l1ke mem-.

bers of refractory material recessed at their edges and interposedbetween the successive convolutions in such" manner as to imbed orenclose the convolutions between them, and stay passing thru saidblock-like mem bers outwardly of the convolutions.

In testimony whereof I afiix my signature.

WILLIAM DOHERTY.

